That is the one. Thank you! One reviewer said it was disappointing as it is for high school students, which was true, as far as I remember. It had cute cartoon

That is the one. Thank you! One reviewer said it was disappointing as it is for high school students, which was true, as far as I remember. It had cute cartoons and such in it. The ideas were interesting but again I was in my early teens. As an adult not sure if I'd have the same reaction to it. Certainly not after paying £30 for it. I still remember some of the solution there, looked at the table of contents and suddenly remembered a lot more, like metal pipe elbow with the steel balls flying to it - use a magnet to build a protective layer of steel balls. Another one is to use blocks of ice to slowly lower a heavy transformer to the ground.